Binding element

ABSTRACT

A binding element including a metal sheet and an intermediate layer secured to the metal sheet. A first glue adheres a first surface of the intermediate layer to the metal sheet, and has a predetermined melting temperature. A second glue is provided on a second surface of the intermediate layer opposite the first surface, and has predetermined melting temperature. The melting temperature of the first glue is higher than the melting temperature of the second glue.

BACKGROUND

The present invention relates to an improved binding element, moreparticularly a binding element of the type whereby the interior of theback is provided with an amount of glue which melts under the influenceof heat and whereby the intention is to apply the edges of a number ofsheets or documents in this melted glue, in such a manner that, afterthe glue has hardened, said sheets or documents are fastened in a solidmanner.

More particularly, the present invention relates to such bindingelement, the back of which is formed by a metal strip which either ornot is folded into a certain shape and whereby said amount of glue isprovided on this metal strip.

It is known that for an ideal binding of sheets, documents or the like,it must be provided for that the so-called binding glue becomes asliquid as water, such that the documents can settle into the bindingglue due to their own weight, without the necessity of tapping on thedocuments in order to insert them into the binding glue.

In this manner, the heating of said binding glue can be stopped at acertain moment, without any other intermediary, after which cooling cantake place.

Only on the basis of said conditions, one may speak of a reallyautomatic binding.

SUMMARY

In a particular embodiment, said back will be realized in a U-shape,whereby the meltable binding glue is provided in the base of said back.

However, an important disadvantage thereof is that the meltable bindingglue does not adhere well to the hard metal back.

Thus, the present invention relates to improvements by which a perfectconnection between said meltable glue or binding glue and said metalback is obtained in a simple manner.

It is known that binding glues which are provided in such aforementionedbinding element or binding file are designed such and show such featuresthat they specifically can glue paper, cardboard or such in a very goodmanner.

The disadvantage thereof is that these binding glues, however, do notadhere well to metal.

At the same time, it is known that the temperature of said binding gluesmay not exceed 130° C., as otherwise possible synthetic materials, suchas PVC, PP or such, which form part of the binding element or thebinding file, might be thermically damaged.

The present problem, thus, is that the binding glue, which really isvery liquid below 130° C., and which glues paper, cardboard and the likein a very good manner, badly adheres to hard metal elements, such as theback of a binding element or binding file.

It is also known that said binding glues, when they glue paper,cardboard and the like in a very good manner and also adhere to metals,such as, for example, steel, in a very good manner, even above 130° C.become so little liquid that the sheets, documents or the like will notsettle into the binding glue by themselves, but will have to be beatenin by tapping on these sheets, documents or the like.

To this aim, for example, first an intermediate layer is applied to themetal, by means of a glue which only melts above 130° C. and which formsa good connection between metal and paper, after which a second glue,which melts below 130° C., is applied on the opposing outer surface ofthe intermediate layer.

The intermediate layer may be formed of paper.

The improvements allowing the aforementioned and other advantages,substantially consist of a part consisting of metal; on this part, anintermediate layer which is adhered to this part by means of ahigh-temperature glue; and on said intermediate layer, a low-temperatureglue.

BRIEF DESCRIPTION OF THE DRAWING

With the intention of better showing the characteristics of theinvention, hereafter, as an example without any limitative character, apreferred form of embodiment of the improvements according to theinvention is described, with reference to the accompanying drawing,which schematically represents the connection of sheets, documents orthe like with the metal back of a binding element, binding file or thelike.

DESCRIPTION OF VARIOUS EMBODIMENTS

In the drawing FIGURE, an embodiment of an improved binding element isshown as having a metal sheet 1 and an intermediate layer 2 secured tothe metal sheet 1. A first glue 3 adheres a first surface of theintermediate layer 2 to the metal sheet 3, and has a predeterminedmelting temperature. A second glue 4 is provided on a second surface ofthe intermediate layer 2 opposite the first surface, and has apredetermined melting temperature. The melting temperature of the firstglue 3 is higher than the melting temperature of the second glue 4.

While any suitable material may be used as the intermediate layer 2, itis preferred that this material is paper in accordance with theembodiment described above.

The present invention is in no way limited to the embodiment describedas an example and represented in the drawings; on the contrary, it maybe realized in a variety of forms, dimensions and compositions withoutleaving the scope of the invention.

1. A binding element comprising: a metal sheet; an intermediate layerhaving opposed first and second surfaces, the first surface adhering tothe metal sheet; a first glue having a predetermined melting temperatureand securing the metal to the first surface of the intermediate layer;and a second glue having a predetermined melting temperature anddisposed along the second surface of the intermediate layer; wherein themelting temperature of the first glue is higher than the meltingtemperature of the second glue.
 2. The binding element according toclaim 1, wherein the intermediate layer is formed by a sheet of paper.3. The binding element according to claim 1, wherein the meltingtemperature of the first glue is above 130° C.
 4. The binding elementaccording to claim 1, wherein the melting temperature of the second glueis below 130° C.